<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
  //ES6 允许给函数参数赋初始值
  //1.形参初始值,一般位置要靠后
  function add(a,b,c=10){
    return a+b+c;
  }
  let result = add(1,2);
  console.log(result);

  //2. 与解构赋值结合
  function connect({host="127.0.0.1",username,password,port}){
    console.log(host);
    console.log(username);
    console.log(password);
    console.log(port);
  }
  connect({
    host: 'localhost',
    username: 'root',
    password: 'root',
    port: 3306
  })
</script>
</body>
</html>